In the hair care industry it is often desired to test the efficacy of a product. Current methods generally comprise treating a hair sample with a hair product, subjecting the hair sample to a single aggressor and measuring the resulting change in condition.
It has now been found that; subjecting a hair sample to multiple aggressors, on multiple days, and measuring the condition, will provide enhanced differentiating data on the condition of the hair and therefore provide a superior assessment of the efficacy of any products used in the hair. Furthermore this is a more realistic and consumer relevant assessment of the condition of hair and efficacy of hair care products.